Pmt Voltage Adjustment - Thermo Scientific 43i Instruction Manual

PMT Voltage
Adjustment
Thermo Fisher Scientific
Use the following procedure to adjust the PMT voltage after replacing the
PMT, High Voltage Power Supply, or switching from standard to extended
ranges or vice versa.
Note: The service procedures in this manual are restricted to qualified
service representatives.
1. Select the SO , range. Refer to "Range Menu" in the "Operation"
2
chapter.
2. Reset the SO BKG calibration factors to 0.0. Refer to "Calibration
2
Factors Menu" in the "Operation" chapter.
3. Reset the SO COEF to 1.000.
2
4. Set the Averaging Time to 10 seconds. Refer to "Averaging Time" in
the "Operation" chapter.
5. Connect the calibration gas and allow the instrument to sample
calibration gas until the reading stabilizes.
6. From the Main Menu, press
to scroll to PMT Supply Settings > and press
The PMT Supply Settings screen appears.
Note If Service Mode is not displayed, refer to "Accessing the Service
Mode" in this chapter, then return to the beginning of this step.
7. At the PMT Supply Settings screen, press
PMT Adjustment.
The Set PMT Voltage - Manual screen appears.
8. At the Set PMT Voltage - Manual screen, use
increment/decrement the counts until the instrument displays the
calibration gas concentration value.
▲
to scroll to Service > press
Model 43i Trace Level-Enhanced Instruction Manual
Servicing

PMT Voltage Adjustment

>
.
▲
to select Manual
to
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